Summary
It was discovered that Tornado incorrectly handled special characters in
HTTP headers. An attacker could possibly use this issue to execute a cross-
site scripting (XSS) attack. This issue only affected Ubuntu 20.04 LTS,
Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, Ubuntu 25.04, and Ubuntu 25.10.
(CVE-2025-67724)
It was discovered that Tornado incorrectly handled repeated HTTP headers.
An attacker could possibly use this issue to cause Tornado to use excessive
resources, causing a denial of service. (CVE-2025-67725)
It was discovered that Tornado incorrectly handled parsing of certain HTTP
header values. An attacker could possibly use this issue to cause Tornado
to use excessive resources, causing a denial of service. (CVE-2025-67726)
Fixed packages 6
| Release | Package | Fixed in |
|---|---|---|
| Ubuntu · 24.04 LTS 24.04:LTS | python-tornado | 6.4.0-1ubuntu0.4 |
| Ubuntu · 25.10 | python-tornado | 6.4.2-3ubuntu0.2 |
| Ubuntu · Pro 16.04 LTS Pro:16.04:LTS | python-tornado | 4.2.1-1ubuntu3.1+esm2 |
| Ubuntu · Pro 18.04 LTS Pro:18.04:LTS | python-tornado | 4.5.3-1ubuntu0.2+esm2 |
| Ubuntu · Pro 20.04 LTS Pro:20.04:LTS | python-tornado | 6.0.3+really5.1.1-3ubuntu0.1~esm3 |
| Ubuntu · Pro 22.04 LTS Pro:22.04:LTS | python-tornado | 6.1.0-3ubuntu0.1~esm4 |